Speed synchronizing device



May 17, 1938. D. E. LEWELLEN ET AL SPEED SYNCHRONIZING DEVICE Filed Sept. 23, 1955 '7 Sheets-Sheet l 04/?0 E.LEWE1.I.EN 5y 1. MOMS/"- LE ELLEN.

s r N ATTORNEYS May 17, 1938. D. E. LEWELLEN ET AL SPEED SYNCHRONIZING DEVICE Filed Sept. 23, 1955 '7 Sheets-Sheet 2 May 17, 1938.

D. E. LEWELLEN ET AL SPEED SYNCHRONI Z ING DEVI CE 7 Sheets-Sheet 5 FiledSepL. 25, 1955 May 17, 1938- D. E. LEWELLEN ET AL 2,117,484

SPEED SYNCHRONIZING DEVICE Filed Sept. 23, 1935 7 Sheets-Sheet 4 IIIUIJU U D [IUD D D y 1938. D. E. LEWELLEN ET AL 2,117,484

SPEED SYNCHRON I Z ING DEVI CE Filed Sept. 23, 1935 7 Sheets-Sheet 5 ATTORNEYS May 17, 1938. D. E. LEWELLEN ET AL 2,117, 4

SPEED SYNCHRONIZ ING DEVICE Filed Sept. 23, 1935 '7 Sheets-Sheet 6 y 1938. D. E. LEWELLEN ET AL 2,117,484

SPEED SYNCHRONIZING DEVICE Filed Sept. 23, 1955 7 Sheets-Sheet 7 Patented May 17, 1938 UNITED STATES SPEED SYNCHBONIZIN G DEVICE Darcy E. Lewellen and Emmons F. Lewcllen, Columbus, Ind.

Application September 23, 1935, Serial No. 41,760

22 Claims.

This invention relates to methods and apparatus for the synchronization of the speeds of two or more devices; and also to the accurate po-- sitioning of the elements thereof.

One object of the invention is to provide. means for synchronizing the speeds of two mechanically unconnected revolving shafts in order to maintain a constant speed relationship between them and also to bring one of the shafts automatically back into synchronism with the other shaft in the event that a speed variation arises between them.

Another object is to provide a synchronizing switch having devices associated therewith by which this synchronization of the different machines or shafts may be brought about.

Another object is to provide apparatus for causing three or more mechanisms to operate not only in synchronism with one another as regards their speeds but also as to the relative positions of the elements in each mechanism so that these elements will remain in the same positional relationship.

Another object is to provide apparatus wherein three mechanisms, such as conveyors, are so arranged that two of the mechanisms serve the third in such a manner that when either of the subsidiary mechanisms is stopped, the other mechanism will immediately and automatically come up to the full speed of the major mechanisms, not only as regards synchronization of its rotating elements but also as regards the positions thereof.

Another object is to provide apparatus wherein three mechanisms, such as conveyors, are so arranged that when all three of the mechanisms are in operation the two auxiliary mechanisms will be automatically caused to run at one-half the speed of the major mechanism, not only as 40 regards the speed synchronization of its rotating elements, but also as regards the positioning thereof. This latter condition is produced by a relay coil which operates a switch arm, one wire from this relay running to one phase of the power line, the other wire running to another phase of thepower line whenever both auxiliary mechanisms are in operation.

In particular it is an object to provide a sys tem containing three conveyors, two of which are arranged to transfer articles to the third conveyor, arrangements being provided wherein each of the minor conveyors runs at half the speed of the major conveyor when both minor conveyors are working or such that when one minor conveyor is stopped, the other minor conveyor is immediately and automatically brought up to the full speed of the major conveyor.

Another object is to provide such an arrange ment of three conveyors as described above wherein each minor conveyor has elements at different positions thereon, arrangements being made such thatthese positioned elements will always remain in the same locations relative to one another regardless of whether one or two minor conveyors are operating. 10

It is another object of this invention to pro vide a series of three mechanisms wherein a major mechanism is served by two minor mecha. nisms, these devices being so arranged that spaced elements on the minor and major con- 15 veyors are brought into the proper positional relationship as well as the speeds being brought into proper synchronization.

Another object is to provide a device for accomplishing the bringing of spaced elements on different mechanisms into positional alignment, as well as bringing the mechanisms into speed synchronization with one another.

Another object is to provide apparatus of the above described nature in which the spaced ele- 25 merits of the different mechanisms are automatically brought into the proper positional relationships before the mechanisms are allowed to start operating synchronously.

Another object is to provide a switch device adapted to control not only the synchronization of different mechanisms as to their speeds of rotation but also to control the relative positions of certain elements in these mechanisms and insure these elements being constantly kept in the proper positional relationships.

Another object is to provide automatic means for bringing the elements of two or more mechanisms into predetermined positional relationships during the operation of the mechanisms in the 4 event that these elements depart from the proper relationships, this being accomplished automatically and speed synchronization of the mechanisms likewise being accomplished automatically after any departure therefrom.

This application is a continuation in part of our co-pending application Ser. No. 752,848, filed November 13, 1934, which matured into Patent No. 2,076,202.

Referring to the drawings:

Figure l is a diagrammatic layout view showing the arrangement of three conveyor systems arranged to operate in speed synchronisrn and in positional agreement.

Figure 2 is a side elevation of the spacer ad- 55 lit by the roaster machine 0.

justment device used in the system of Figure Figure 3 is a right hand endelevation of a spacer adjustment device shown in Figure 2.

Figure 4 is a side elevation on the opposite side from the view' shown in Figure 2.

Figure 5 is a plan view of the spacer adjust== merit device shown in Figures 2 to 4.

Figure 6 is a plan view with the casing in section of the space control contactor used in the system shown in Figure 1.

Figure '"l is a vertical section through space control contactor shown in Figure 6 talren along the line l--l thereof.

Figure 8 is a cross-section along the line -8 in Figure l.

Figure 9 is a cross-section along the line of Figure I.

Figure id is a simplified wiring diagram showing the relative positions and arrangement oi the different electrical units enriployed in the arrangement of this invention shown Figure Figure ii is a schematic wiring diagram show ing the complete connections of the device of Figure ill.

l-encral construction and arrangement The synchronization system shown Figure l in general embodies three different machines such as the conveyors generally A, El and C. machine C is a master machine which is manually controlled to its whereas the machines A and B are subsidiary machines controlled both as to position and speed in particular the n.achine C consists of a variable speed transmission Elli having a driving motor driving the input shaft 2% thereof through the driving chain 26 1 (Figure i). This variable speed transmission Elli is of the type described in U. 55. Patent to Lewellen, et al, No. 2,,ll'l62ll2, dated April 6, 193?, is similarly provided with a pilot motor or speed adjus ing motor 2% arranged to drive the screw shaft by means of the drive chain ml. The actuation of the pilot motor 205 causes the variable speed transmission to be adjusted a mannersimilar to that already described in the above mentioned Lewellen, et al Patent No. 2,,lll6,22

by rotating the screw shaft 2%. The hand wheel 2% on the screw shaft M6 may optionally be used to adjust the variable speed transmission dbl manually.

The pilot motor or speed adjusting motor 2% is controlled through the line 2% connected to the push button station 2 it having the push buttons El [1 and 2112. By depressing the push button 20 l, the pilot motor 2% is caused to operate in a direction of increasing the output speed of the variable speed transmission, whereas the depression of the push button 2 it? causes a decrease in the output speed. in this manner the adjustment of the master variable speed transmission illll' may be remotely controlled from any desired point. To the output tilt is connected an electrical tachometer Zld having a line M running to the tachometer indicator 2H5. lhe latter shows the output speed at which the output shaft 263 of the master variable speed transmission ml is being operated, enabling the operator to adjust the machine to any desired speed. The output shaft 2153 is connected to the input shaft 2H oi the reduction unit 2l8, the output shaft 2E9 or which carries the sprocket 220, around which passes the master conveyor chain 22 l. The latter is provided at spaced intervals with lugs 222, an

interval or ten feet being found convenient in one installation. The master conveyor chain 226 by means of the lugs 222 operates trolleys arranged on tracks (not shown) and pushed by the lugs 222.

in a particular installation in a packing house, the master conveyor 222i is used to transport carcasses of animals which have been slaughtered. The master conveyor 2M passes around various guide sprockets 223 so that the conveyor is guided its course in any desired manner.

Also connected to the output shaft tilt of the master variable speed transmission by the drive chain 2% is a master synchronizing transmitter called a Selsyn sender by workers in the electrical art. nutter operates on the synchronous current principle and serves to control other synchronizing receivers in other parts of the apparatus as mentioned below.

Associated with the master synchronizing transmitter is a synchronizing differential called a Selsyn differential by workers in the electrical art. The synchronizing transmit i226 and the differential 2226 are of a conven tional type, the details of which form no part of present invention.

Arranged adjacent the conveyor 22!! is the conveyor chain 2% which passes around guide sprockets 23 in any desired path. The conveyor chain is associated with the subsidiary machine A and in one part of its course passes aroimd a guide sprocket arranged upon a shaft 233 connected to an arm carrying the shaft 2535 upon which is mounted the transier table The latter serves the purpose receiving the articles the trolleys accompanying the conveyor chain 23d and transfers them to the master conveyor chain 2'26, The subsidiary conveyor chain 23% is driven by the variable speed transmission 223i from the motor 238 through the driving chain 2339i, connecting to the input shaft 2% thereof. As in the case oi the variable speed transmission till, a pilot inctor 2 3i operates the screw adjustment shaft 242 through the driving chain 2%, the shaft 242 likewise having the hand wheel Md. The output shaft 265 of the variable speed transmission 223i is connected to one side of synchronizing switch 2 16 similar in form and arrangement to the synchronizing switch described in the previously mentioned U. S. patent to Lewellen, et al., No. 2,076,262, dated April 6, 1937.

The opposite side or" the synchronizing switch 266 is connected to the shaft ri l-l driven by the synchronizing receiver M8, known to electrical workers by the name Selsyn receiver". The latter is, of a conventional type and its details form no part, of the present invention. The output shalt M5 of the variable speed transmission 231 is connected to the input shaft 258 of the spacer adjustment device generally designated 25E and shown in detail in Figures 2 to 5 inclusive. This spacer adjustment device 255i will be described in detail below, and serves to bring the. lugs 252 upon the subsidiary conveyor chain 230 and the lugs 25$ upon the subsidiary conveyor chain 254 into a predetermined positional relationship with the lugs 2212 upon the master conveyor chain 22l and does this without disturbing the speed synchronization thereof.

From the spacer adjustment device 25!, the shaft 255 leads into the reduction unit 256, and the output shaft 251 carries the sprocket 258 arranged to drive the subsidiary conveyor 230. Also extending from the spacer adjustment device 25l is the shaft 259, terminating in the bearing 26!! This master synchronizing transupon the variable speed transmission 261. The shaft 259 is connected to the output shaft 262 by the drive chain 263.

The shaft 259 is also drivingly connected through the drive chain 263 to one side of the synchronizing switch 264, the Opposite side of which is connected through the shaft 265 to the synchronizing receiver 266, Thelatter is likewise of the type called a "Selsyn receiver by workers in the electrical art.

The variable speed transmission 26l is likewise provided with a screw adjustment shaft 261 having a hand wheel 268 and a drive chain 269 connecting it to the pilot motor 216. The driving motor 211 is drivingly connected to the input shaft 212 of the variable speed transmission 26l by the drive chain 213. The variable speed transmissions 26i and 231 are likewise. of a type similar to that previously mentioned and similarly controlled oy their pilot motors. The pilot motor 2 is controlled as to its actuation by the synchronizing switch 246 responsive to the synchronizing receiver 248, whereas the pilot motor 216 is similarly controlled by the synchronizing switch 264 responsive to the synchronizing receiver 266. The synchronizing receivers 248 and 266 are in turn controlled by the synchronizing transmitter 225 through the differential 226.

The differential 226 serves to drive the subsidiary conveyor chain 236 or 254 at the same speed as the master conveyor chain 22l when only one of the subsidiary conveyor chains is being operated. When both subsidiary conveyor chains 236 and 254 are operated, however, each is driven at half the speed of the master conveyor chain 22I through the action of the differential 226.

The synchronizing receivers 248 and 266 are responsive to the synchronizing. transmitter 225 to maintain exactly the same rotational speeds and consequently insure the same conditions of operation for the mechanism controlled thereby. The output shaft 262 pf the variable speed transmission 26l is connected to the input shaft 214 of the reduction unit 215 having its output shaft 216 carrying a sprocket 211 arranged to drive the subsidiary conveyor chain 254. The guide sprockets 218 serve to guide this chain at various points in its course.

The spacer adjustment device The spacer adjustment device 25l, more particularly shown in Figures 2 to 5 inclusive, consists of a base or pedestal 286 arranged to rotatably receive the planetary transmission housing 28l. The transmission housing 28I contains planetary gearing of a conventional type, to the opposite sides of which the shafts 255 and 256 are connected respectively. The housing 28I carries the sprocket 282 (Figure 4) which is connected by the sprocket chain 283 to the sprocket 284 upon the shaft 285 leading from the gear reduction unit 286.

The gear reduction unit 286 is connected to the motor 281, By this mechanism the motor 281 is caused to rotate the planetary transmission housing 28l within the pedestal or frame 286. By revolving the planetary transmission housing 28l, it is possible to change the positional relationship between the sprocket 258 upon thereduction unit 256 andthe variable speed output shaft of the variable speed transmission 231 without changing their speeds.

Projecting from the gear reduction unit 286 is the shaft 286 carrying the brake drum 289 engaged by the brake bands 296 (Figure 3) on the brake levers 29! and 292. The latter are pivotally supported at 293 and 294 respectively and their upper ends are interconnected by the rod 295 having a spring 296 abutting at one end against the nut 291 and at the other end against the brake lever 292. The arm 298 connected by the link 299 to the armature 366 of the solenoid 36! serves to actuate the brake. when the driving motor 281 is energized, the brake is instantly released by the action of the solenoid 3M and the brake bands 296 freed from engagement with the brake drum 289.

Mounted on the pedestal 286 is a shelf 365 upon which are arranged the speed reduction units 366 and 361 respectively. The previously mentioned shaft 259 coming from the variable speed transmission 261 is rotatably supported in the bearing block 368 (Figure-3) and carries a sprocket 369 arranged to drive a sprocket 3l6 on the input shaft 3| I of the speed reduction unit 361 by means of the sprocket chain 3I2. The output shaft -3I3 of the speed reduction unit 361 carries the sprocket 3, which is drivingly connected to the sprocket 3| 5 of the space controlled contactor 3l6 by the sprocket chain 3l1.

Similarly, the other sprocket 3I8 of the space controlled contactor 3l6 is drivingly connected by the sprocket chain 3 i 9 to the sprocket 326 upon the output shaft 32l of the speed reduction unit 366. The input shaft 322 of the latter carries the sprocket 323'which is drivingly connected by the sprocket chain 324 to the sprocket 325 upon the shaft 255.

Space control contactor The space control contactor 3| 6 has for its purpose the delaying of the start of one of the minor transmissions or machines until the moving parts of the machines running have arrived at the proper relative positions with reference to the machine to be started; and also for the pur-' pose of correcting 'any drifting out of position which may occur during the operations of the machines.

The space'control contactor consists of P supporting plate 336 having an inwardly projecting sleeve-like portion 33! (Figure 7). Rotatably supported within this sleeve-like portion 33l upon the anti-friction bearings 332 is a sleeve 333 carrying the sprocket 3l5 previously mentioned.

The collar 334 threadedly engaging the sleeve 333 maintains the sprocket 3l5 and the inner race of one of the anti-friction bearings 332 in proper relationship. The opposite end of the sleeve 333 carries an outer sleeve 335 subsequently to be described, this being held in place by the threaded collar 336 upon the end of the sleeve. Within countersunk portions in the ends of the collars 334 and 336 are arranged the anti-friction bearings 331,. which serve to rotatably support the shaft 338 upon which the sprocket M8 is held by means of the threaded nut 339.

The shaft 338 rotates freely within the sleeve 333 by means of the anti-friction bearings 331 and carries a pair of disks 346 and 341 on the end oppositethe sprocket M8. The disks 346 and 34I are held in position by the threaded not 342.

- The disk 346 is provided with a cylindrical flange Consequently,

portion 341 arranged in a similar manner upon iii) Gn the outer sleeve 335 mounted upon the inner sleeve (Figure 7) are mounted the outer projecting arms 35d which support at their outer ends the switch dist: 35H (Figure 6). lvlounted upon the switch disk 35i are the switch supporting posts 352, 353 and 354i (Figures 6, El and 9). The switch post 354 serves to support the moving elements of the switch 355 having the movable contact 356 and urged into action by the spring 35l under the influence oi the cam portion dill (Figure 9). The switch disk 3M also carries the fixed contact 358 arranged to engage the movable contact 358 and mounted upon the arm Consequently, as the cam disk 3 1i rotates upon the shaft the successive engagementof the cam portion Ml with the switch 355 will cause the movable contact 356 to become engaged and disengaged with the fixed contact 358.

Similarly, the post 352 carries a switch Silt (Figure t) having an operating roller 36i arranged to engage the cam portion 344 upon the cam dish 34d and actuated by the spring 362. The switch 360 is provided with a movable contact 363 which is forced into engagement with a fixed contact 354 upon an arm 365 supported by the switch disk 35E in response-to the engagement and disengagement oi the cam portion 344 with the switch actuating roller 3%. Diametrically opposite the switch 3% and mounted upon the switch post 353 is the switch 366, the movable elements of whichcarry the movable contact ilt'i engaging the fixed contact 368 upon the arm 3% attached to the switch disk 3M (Figures 6 and 8). The switch is actuated in one direction by the spring Slit and in the other direction by the cam element 3% upon the cam dish 340.

The switches 355 and 366 are of a snap action type arranged to close and open the contacts with a rapid motion so as to reduce arcing to a minimum. The details oi these switches and of the remaining switch 360 form no part of the present invention and are of a conventional type.

Mounted on the outer sleeve 335 are insulating rings 3'ii carrying the collector rings 312, 3W,

'314, its and are respectively (Figure 7). These collector rings are respectively engaged by the contact fingers 3H, 3'l8, 3H3, 380 and 38L The,

collector rings are connected to the switch elements in a manner described below and in this manner the circuit is maintained between the device and the outside electrical units.

The fixed contacts 368 and 35B are interconnected by the common lead 382 (Figure ii) and this common lead is connected by the line 383 to the collector ring 314. Similarly the fixed contact 384 of the switch 3% is connected by the line 304 to the collector ring H3. The movable contact 363 of the switch 366 is connected to the collector ring 312 by the line 385. The movable contact 355 of the switch 355 is connected by the line 306 to the collector ring 315. Finally the movable contact 361! of the switch 365 is connected to the collector ring 3% by the line 38l.

It will be observedthat the contacts 363 and 364 of the switch 360 are engaged while the contacts 367 and 363 of the switch 366 are disenof the driving motors of these conveyors until this positioning has taken place.

of the switch 355 are engaged when the shafts or moving parts are not properly positioned.

The switch 360 causes the parts to be properly spaced or positioned before thev driving motors are brought into operation whereas the switches 366 and 355 serve to correct any drifts from posi tion which may take place during the operation of the device according to the operation of the electrical device hereinafter described.

The internal parts of the space control contactor 3H5 are protected from dust and injury by means of the casing 388. The conduits 389 serve to convey the previously mentioned leads from the various switch contacts to the collector rings.

. the operation of a preferred embodiment of the invention is shown in simplified form in Figure 10 and in complete form in Figure 11. As shown in Figure 10, the respective driving 'motors 202, 238 and tilt of the conveyor units A, B and C (Figure l) are provided with starting switches 400, dill and 402 respectively, these starting switches being of the magnetically operated type receiving power current from the power lines 403, 3M and 405. The starting switch Mill is operated by; the starting switch buttons 4% and stop switch buttons 401, these-being placed at any desired points.

The master conveyor unit C, as has been previously described, is provided with a pilot motor 205 which is under the control of a double magnetic multiple pole contactor 408, which in turn is operated by the push buttons 2| l and M2. The push button 2 operated the contactor 408 to cause the pilot mtor205 to adjust the variable speed transmission 20! so that it increases its speed, whereas the push button 2I2 operates the pilot motor 205 in the opposite direction to decrease the speed. The push button 2i i will therefore be termed the fast speed push button and the push button 2 l2 the slow speed push button.

The master or major conveyor unit C is likewise equipped, as previously stated, with a Selsyn transmitter 225 and a Selsyn differential 226 controlled by the double magnetic multiple pole contactor 409 and the single pole magnetic relay 0.

These electrical units in the master or major conveyor unit C are interconnected in the manner shown in Figure 11. The magnetic relay M0 serves to prevent the operation of both conveyor units A and B at a double speed, reserving this double speed for the occasion when but one or these minor conveyors is in operation.

The minor conveyor unitsA'and B are provided with starting switches 4M and 402 controlling their driving motors 238 and 2H and likewise with the double magnetic multiple pole contactors 4H and H2, and also the multiple pole single contactors 4l3and M4, the controllers M and M6, and the multiple pole single contactors 4H and 8. I P

The pilot motors 24! and 210 of the minor conveyor units A and B are controlled respectively by the double magnetic multiple pole contactors 489 and 420 in accordance with the operation of quire a resetting by means of these switches.

the rotary contactors or' synchronizing switches 249 and 264 previously described.

The minor conveyor unit A is provided with the rotary space control contactor 3H5 associated with the spacer adjustment device 25l, these being connected to the spacer selector or double magnetic multiple pole contactor 42l with which is associated the time delay relay 422. The motor 201 which operates the spacer adjustment device 25l is controlled by the double magnetic multiple pole contactor 423 with which is associated the single pole magnetic relay 424, these units being connected in the manner shown in Figures 10 I and 11 and operating in a manner hereafter described.

The minor conveyor units A and B are controlled by the corresponding pairs of manual switches425 and 425 or 421 and 428 or 429 and 430 in a manner subsequently to be described, these switches being arranged to the right of the assembly of electrical units for each conveyor unit as shown in Figure 10. The manual switches 43! and 432 are also provided in connection with the minor conveyor unit A and adjacent the manual switches 425, 421 and 429 for a purpo hereinafter described.

Signal lamps 433 associated with the various manual switches indicate the condition of the circuit and the manner in which it is being controlled at any instant.

As previously stated, the electrical system is arranged to operate in two different manners. If both of the minor conveyors A and B are operating, then each operates at half speed relatively to the major conveyor C, whereas if only one of these minor conveyors is operating, it is automatically arranged to operate at full speed.

The manual switches 425, 421 and 429 serve for setting the operation of the driving motors of the conveyor units A and B. The closing of the switch 425 or 426 starts the particular driving motor 238 or 2H through the starting switches 40l or 402 and contactors 4 or 2 regardless of whether any of the other units are running or are stopped.

On the other hand, the closing of either the manual switches 421 or 428 stops the particular driving motor 238 or 21! respectively regardless of whether the driving motor was operating in synchronism with any of the other conveyor units or whether it was running independently. Finally, the closing of either of the manual switches 429 or 430 causes the minor conveyor units A or B to operate in synchronism with the major conveyor unit C.

The signal lamps 433 indicate at a glance which of these switches is closed and what setting has been obtained. The particular setting of these switches 425 to 430 inclusive may be accomplished regardless of whether the particular unit to which the switch is attached or any of the other units are running or halted and the starting or stopping of any of the other units does not re- If the manual switch 425 is depressed while the minor conveyor unit is operating in synchronism with the .major unit C, then no further speed change will be obtained except by hand. It the button 429 is depressed while the minor conveyor unit is running independently of the others or is stopped, then theunit A will automatically come into synchronism.

The controllers M5 and 6 provide the impulse circuit through the rotary contactors 246 and 264 of the speed synchronizing control for-the minor conveyor units A and B. As previously stated, the Selsyn transmitter or transmitter and differential causes the Selsyn receivers to run at the normal or double speed rates respectively in synchronism with the Selsyn transmitter and differential, the latter being driven from the variable speed shaft of the conveyor unit C. Each Selsyn receiver unit 266 or 248 rotates half of its rotary contactormechanism 246 or 264, the other half being rotated from the variable speed shaft of the variable speed transmission 23! and 26l in the manner previously described. Power is supplied to the Selsyn transmitter unit 225 only when the driving motor 202 is running. The switch buttons 43I and 432 operate the double magnetic multiple pole contactor 409 of the major conveyor unit C. One side or the other of the circuits through the contactor 409 is always engaged with the major unit C or either of the minor units A or B is operating or stopped. One of these circuits directly connects the Selsyn transmitting circuit from the Selsyn transmitter 225 to the Selsyn receivers 248 and 266 whereas the other circuit connects the Selsyn transmitting circuit from the Selsyn transmitter 225 by way of the Selsyn differential 226 to the Selsyn receivers 248 and 266.

The depression of the switch button 432 causes the contactor 409 to operate the Selsyn receivers 248 and 265 at the normal speed. If all of the conveyor units A, B and C are shut down or if the major conveyor unit C and onlyone of the minor conveyor units A or B are operating in synchronism, the depression of the push button 43l will operate the contactor 409'to cause the Selsyn transmitting circuit to pass through the Selsyn differential 226 and cause the Selsyn receivers 248 and 265 to. operate at the double rate. If both of the minor conveyor units A.and B are running in synchronism with the major conveyor unit A, the contactor 409 can not be set for double speed operation, for if the major conveyor C and one of the minor conveyors A or B are operating in synchronism and the contactor 409' has been set for operating the Selsyn receiver 248 or 206 at the double rate, the coming of the second minor conveyor unit A or B into synchronism causes the contactor 409 to be automatically reset to connect the Selsyn transmitting circuit for operating the Selsyn receivers 248 and 296 at the normal rate. set for this normal rate, the starting or stopping oi any of the units does not require a resetting of the contactor 409. If the '-switc h button 43l has been depressed to set the contactor 409 for the double rate while all of the conveyor units A, B and C are shut down, and allof these conveyor units are then started to operate in synchronism, the contactor 409 is automatically reset for the normal speed rate.

The contactor 409 can not be set for the double speed rate except when only one of the minor conveyor units A or B is operated in synchronism with the major conveyor unit C and the starting.

When the contactor 4091s.

prevented by the operation of the relay M0 associated with the major conveyor unit C and the contactor 409.

The multiple pole single magnetic contactors 4|! and M8 connect both the power and Selsyn transmitting circuits to the Selsyn receivers 248 or 266 only when the particular minor conveyor unit A or B is operating in synchronism with the major conveyor unit C. When the particular minor conveyorunit A or B is shut down or when itis operating independently of the others, the circuits to its Selsyn receiver are open.

The double magnetic multiple pole contactors 4 or 412 are arranged to be disengaged by the operation of the switch buttons 421. or 428 respectively. When this occurs, the circuits through these contactors 4| I or 2 are open and the particular unit will not operate. With thecircuit closed by either of the switchbuttons 425 or 426 for independent operation of the minor conveyor unit A or B, the starting switch l or 402 is operated directly. With the circuits through the contactors 4l| or 412 set for synchronous operation by depressing the switch buttons 429,

or 430, however, then the circuits are closed through the contactors H3 or iii and ill or Mt while the particular unit, A or B is operating. The operation of the contactors M3, ti t, Ml and t i it when starting is dependent upon the sequence of the spacer selector contactor-Ml and time relay M2.

With either of the minor conveyor units set for synchronous operation withthe major conveyor unit C and running, speed synchronisin therehetween is obtained by the rotary contactors tit and 26E as described in the previously mentioned Patent No. 2,0762%. With half of the rotary contactors 24s or 2% rotating at a speed corresponding to the speed of the major conveyor C, a slightly faster or slower operation of the minor conveyor transmissions rotates the other half or" the contactors 2% or 2M to bring into engagement the circuit receiving impulses from the controllers M5 or M6.

- This causes the contactcr M9 or G lli to operate and energize its pilot motor h ll or Eli] during the impulse interval. This incremental correction of the minor conveyor transmission speed setting returns the minor conveyor to speed synchronism with the major conveyor (53.

ll rapid speed change such as would he necessary when the major conveyor speed is altered manually loy the operation or the manual switches ill or tilt is obtained by the continuous operation of the contactors M9 or Mil and their pilot motors M6 or Elli through the secondary circuit of the rotary contactor 2% or As the speed setting of the particular minor conveyor approaches synchronisxn, the continuous speed changing circuit of the rotary contactors M6 or set is disengaged, after which the incremental operation of the pilot motor 2M or 2% through.

the rotary contactor and controller circuit thereof returns the minor conveyor speed to synchronism in the above manner.

With the contactor lit set for synchronous operation, the engagement of the start louttonv QJL 17,484

gagement of one of the start buttons 406 starts driving motor 202 of conveyor C as previously described and starts conveyor 8 by operating the other half of the contactor 42!.

When one of the minor conveyor units A or B has been stopped or has been operating independently, and is reset by depressing button 429 or 430 to operate in speed synchronism with the major conveyor C and the other minor conveyor, the latter of which is already operating, the previous operation of the half of the contactor 42! has set circuits which prevent the immediate closing of the other half of the contactor 42I until the starting contacts 363 and 364 of the rotary space control contactor 3t6' come into engagement.

The engagement of these starting contacts occurs at the instant that the chain lug 253 of the conveyor unit B, which is assumed to be operating, reaches the point where its position laps the chain lug 252 of the conveyor unit A, which is assumed not to be running. The consequent closing of the other half of the contactor 42l following the engagement of the starting contacts 363 and 36 i of the rotary space control contactor 3M5 closes the circuits for operating the contactors M3 or M4 oi the particular minor including the multiple pole single contactors 4H 4 and Gill, the Selsyn transmitter 225 and receivers 2G8 and 2266; the double magnetic multiple pole contactors M9 and Mil; the pilot or speed adjusting motors 2M and no; and the rotary contactors 2G6 and 26 i immediately function to obtain speed synchronism between the conveyors in the manner previously described.

The arrangement of the circuit requires that both of the minor conveyor units A and 13 must he running in order to restore the predetermined space relationship between the conveyor chain lugs and the circuit being through the multiple pole single contactors M3 and 6M and the single polemagnetic relay The relay 626 also operates to prevent a space correction while the speed synchronising units are operat- .ing through the circuit from the relay its to the pilot motor.

With the speed s nchroinzed and a space correction required, then the circuits operating by the functioning of the second set of contacts of the rotary space control contactor tit are brought into operation, these losing the contacts 856 and 3&8 or Sill and 3368 (Figures 8 and 9).

When this occurs, the double magnetic multiple pole contactor M3 operates the transmission rotating motor Zlll to rotate the planetary transmission 282 and properly position the conveyor chain lugs and 253 relatively to one another. lf/hen the chain lug 252 of the minor conveyor unit A-has been properly set ahead or back by means of this control arrangement, the opera tion of the transmission rotating motor 2817 automatically stops through the action of the rotary space control contactor M6. The operation of the latter may be interrupted at any time by the operation of the speed synchronizing control of the minor conveyor unit A or by stopping either one of the minor conveyor units A orB.

With all three of the conveyor units A, B and C stopped and with both of the minor conveyor units A and B set for synchronous operation, when the start button 406 is depressed to start all three units, the major conveyor driving motor 202 and the driving motor 2' of the minor conveyor unit B will start operation at once. As soon ,as the lugs 253 of the conveyor chain 254 in the minor conveyor unit B have moved to the proper positions relatively to the lugs 252 on the chain 230 of the minor conveyor unit A, the driving motor 238 of the minor conveyor unit A then automatically starts in the manner previously described.

The time" delay relay 422 performs this func- 'iJlOll of preventing the starting of the two minor conveyor unit driving motors 238 and 2H when it is desired to operate both minor conveyor units at the same time. The time delay relay thus causes the starting motors 2H and 238 to start with a time interval between them.

It will be observed that the contactors 409, 4, M2, M3, 4H, H1, H8 and "I are provided with holding circuits. All of the double contactors except 42l are also mechanically interlocked in addition to the electrical interlocks provided for several of the circuits.

.It will be understood that we desire to com- I 'prehend within our inventionsuch modifications as may be necessary to adapt it to varying conditions and uses.

'Having thus fullydescribed our invention, whatwe claim as new and desire to secure by Letters Patent, is: I

1. A synchronizing system including a major machine and a plurality of minor machines, means for varying the speeds of said minor machines independently of each other and of said major machine, means associated with said minor machines and responsive to the speed of said major machine for synchronizing the speeds thereof with the speed of said major machine, and means associated with said minor machines for maintaining substantially constant relative positions of a moving element of each minor machine.

2. A synchronizing system including a major machine and a plurality of minor machines, means for varying the speeds of said minor machines independently of each other .and of said major machine, means associated with said minor machines and responsive to the speed of sa d major machine for synchronizing the speeds thereof with the speed of said major machine, moans associated with said minor machines for maintaining substantially constant relative posi- ,tions of a moving element of each minor machine,

and means for automatically bringing the speed of ,one of said minor machines back into synchronism with said major machine upon the occurrence of a departure from synchronism therewith.

3. A synchronizing system including a major machine and a plurality of minor machines,

means for varying the speeds of said minor machines independently of each other and of said major machine, means associated with said minor machines and responsive to the speed of said major machine for synchronizing the speeds thereof with the speed of said major machine,

means associated with said minor machines for maintaining substantially constant relative positions of a moving element of each minor machine, andmeans for automaticallybringing the speed of both of said minor machines back into synchronism with said major machine upon the occurrence of a departure from synchronism therewith.

4. A synchronizing system including a major machine and a plurality of minor machines, means for varying the speeds of said minor machines independently of each other and of said major machine, means associated with said minor machines and responsive to the speed of said major machine for synchronizing the speed thereof with the speed of said major machine, and means associated with said minor machines for maintaining a moving element of each of said minor machines in a predetermined positional relationship.

5. A synchronizing system including a major machine and a plurality of minor machines, means for varying the speeds of said minor machines independently of each/other and of said major machine, means associated with said minor machines and responsiveto the speed of said major machine for synchronizing the speed thereof with the speed of said major machine, means associated with said minor machines tending to maintain a moving element of each of said minor x machines in a predetermined positional relation-.

ship, and means for automatically bringing one 01' said minor machines back into said predetermined positional relationship upon the occur rence of a departure therefrom.

6. A synchronizing system including a major machine and a plurality of minor machines, means associated with said minor machines and responsive to the speed of said major machine for synchronizing the speeds thereof with the speed of said major machine, means associated with' said minor machines for maintaining a moving element of each of said minor machines in a predetermined positional relationship, and means k for bringing about a positional readjustment of said moving elements without altering the speed synchronization thereof other than during the period of operation of said positional readjustment means.

'7. A synchronizing system including a major machine and a plurality of minor machines, means associated with said minor machines and responsive to the speed of said major machine for synchronizing the speeds thereof with the speed of said major machine, means associated with said minor machines for maintaining a moving element of each of said minor machines in a pre; determined positional relationship, and means for positionally readjusting said moving elements, said readjusting meansibeing arranged to maintain said speeds in substantially unvarying relationship other than during the period of operation of said readjusting means.

8. A synchronizing system including a major machine and a plurality of minor machines, means associated with said minor machines and responsive to the speed of said major machine for synchronizing the speeds thereof with the speed of said major machine, means associated with said minor machines for maintaining a moving element of each of said minor machines in a predetermined positional relationship, means for halting one of said minor machines while ma ntaining the other minor machine in operation, means for restarting said halted minor mach ne. and means for delaying the application of the starting of said minor machine until the completion of the positional readjustment of its moving element with the moving elements of the other minor machine.

9. A synchronizing system including a major machine and a plurality of minor machines, means associated with said minor machines and responsive to the speed of said major machine for synchronizing the speeds thereof with the speed of said major machine, means associated with saidminor machines for maintaining a moving element of each of said minor. machines in a. predetermined positional relationship, means for halting one of said minor machines whilemaintaining the "other minor machine in operation, and means for automatically bringing the other minor machine to a readjusted speed relatively to said major machine to compensate for the stoppage of the first mentioned minor machine.

10. A synchronizing system, including a major machine and a plurality of minor machines, means associated with said minor machines and responsive to the speed of said major machine for synchronizingthe speeds thereof with the speed of said major machine, means associated with said minor machines for maintaining a moving element of each of said minor machines in a predetermined positional relationship, and means operative upon energizing said system to bring said moving elements into said predetermined po sitional relationship prior to starting the combined rotation of said moving elements.

11. A synchronizing system including a major machine and a plurality of minor machines, means for varying the speeds of said minor machines independently of each other and of said major machine, means associated with said minor machines and responsive to the speed of said major machine for synchronizing the speeds thereof with the speed of said major machine, means associated with said minor machines for maintaining a moving element of each .of said minor machines in a predetermined positional relationship, and manually controlled means for varying the speed of said major machine whereby to automatically alter the speeds of said minor machines into synchronism with said major machine.

12. A synchronized conveyor system comprising a major conveyor and a pair of mechanically disconnected minor conveyors, variable speed means arranged to drive said minor conveyors independently of each other and of said major conveyor, means associated with said major and minor conveyors for synchronizing the speeds thereof with one another, and means for automatically maintaining said minor conveyors in a predetermined positional relationship.

13. A synchronizing system including a major machine and a pair of minor machines, said minor machines having moving elements to be maintained in predetermined, positional relationships, and means responsive to the halting of one of said minor machines for automatically increasing the speed oi the other minor machine to a different predetermined relationship with said major machine whereby to compensate for the stoppage of said minor machine.

14. A synchronizing system comprising a major machine and a pair of minor machines, each of said minor machines having a moving element arranged to be maintained in a predetermined positional relationship, said minor machines being arranged to cause their moving elements to serve the moving element of said major machine in alternate sequence, and means responsive to the halting of one of said minor machines to increase the speed or the other minor machine to a different predetermined relationship with said major machine whereby to cause the minor machine which is operating to serve the major machine in the same manner as the two minor machines previously operating. N

'15. A synchronized conveyor system including a major conveyor and a pair of mechanically disconnected minor conveyors, variable speed means arranged to drive saidminor conveyors, means associated with said major and minor conveyors for synchronizing the speeds thereof according to a predetermined arrangement, and

means for automatically maintaining said minor conveyors in a predetermined positional relationship relatively to each other, said position maintaining means being arrangedl to operate prior to said speed synchronizing means whereby to cause said conveyors to come into proper positional relationship before synchronization thereof.

16. A synchronized conveyor system. comprising a major conveyor and a pair of mechanically disconnected minor conveyors, variable speed means arranged to drive said minor conveyors independently of each other and of said major conveyor, and means automatically responsive to a departure from a predetermined positional relationship between the two minor conveyors to operate one of said minor conveyors relatively to the other minor conveyor to bring the minor conveyors back into the predetermined arrangement. r

17. A synchronized conveyor system comprising a major conveyor and a pair of mechanically disconnected minor conveyors, variable speed means arranged to drive said minor conveyors, means automatically responsive to a departure from a predetermined positional relationship between the two minor conveyors to operate one of said minor conveyors relatively to the other minor conveyor to bring the minor conveyors back into the predetermined arrangement, means for starting and stopping said minor conveyors, and means for preventing the operation of the starting means for one of said minor conveyors until the positioning means therebetween has operated to position said conveyors according to said predetermined arrangement.

18. A synchronized conveyor system comprising a major conveyor and a pair of mechanically disconnected minor conveyors, variable speed means arranged to drive said minor conveyors, means automatically responsive to a departure from a predetermined positional relationship between the two minor conveyors to operate one of said minor conveyors relatively to the other minor conveyor to bring the minor conveyors back into the predetermined arrangement, means for starting and stopping said minor conveyors, means for preventing the operation of the start-- ing means for one of said minor conveyors until the positioning means t'nerebetween has op-' erated to position said conveyors according to said predetermined arrangement, and means for automatically bringing said minor conveyors back into agreement with said predetermined positional arrangement upon a departure therefrom.

19. A synchronized conveyor system compris} ing a major conveyor and a pair, of minor conveyors, variable speed transmissions arranged to drive said minor conveyors, means associated with said major and minor conveyors for synchronizing the speeds thereof with one another, motors for operating said transmissions, means for starting said motors, means for causing the major conveyor motorvand one of said minor conveyor motors to start in response to the op- 'eration of the starting means therefor, and means for delaying the operation of the starting means for the other minor conveyor driving motor until the first-mentioned minor conveyor moves into a predetermined positional relation ship with the last-mentioned minor conveyor.

20. A synchronized conveyor system comprising a major conveyor and a pair of mechanically disconnected minor conveyors, variable speed means arranged to drive said minor conveyors, means associated with said minor conveyors for automatically synchronizing the speeds of said minor conveyors with the speed of said major conveyor, and repositioning means automatically responsive to a departure from a predetermined positional relationship between the two minor conveyors to operate one of said minor conveyors relatively to the other minor conveyor to bring the minor conveyors back into predetermined positional relationship, said repositioning means being arranged to be operative only after speed synchronism is reached.

21. A synchronized conveyor system comprising a major conveyor and a pair of mechanically disconnected minor conveyors, variable speed means arranged to drive said minor conveyors, means associated with said minor conveyors for automatically synchronizing the speeds of said minor conveyors withthe speed.

of said major conveyor, repositioning means automatically responsive to a departure from a predetermined positional relationship between the two minor conveyors to cause one of said minor conveyors to move relatively to the other minor conveyor into said predetermined positional relationship, and means for delaying the operation of said repositioning means responsive to the reaching of a condition or speed sync-hmnism of said shafts.

22. A synchronizing system for synchronizing a plurality of machines hoth as to speed and relative positions of their moving parts comprising a plurality of machines, means assoc ted with one machine and responsive to the speed of the other machine for synchronizing the of said first machine with the speed of said second machine, means associated with said machine for maintaining a substantially constant position of a moving element of said first machine relatively to a moving element of said second machine, means for halting one of said machines while maintaining the other machine in operation, means for re-starting said halted machine, and means for delaying the starting of said halted machine until the completion of the positional readjustment of its moving element with the moving element of the operating machine.

DARCY E. LEWELLEN. EMMONS F. LEWELLEN. 

